Patent GB-375940-A (GB)
Title: Improvements in and relating to method and apparatus for humidifying and cooling theair of an enclosure
IPC: F24F3/14
Filed: 1931-05-07
Abstract: 375,940. Thermostats. HUGHES, R. M., 72, Cannon Street, London.-(Parks- Cramer Co. ; 294, Washington Street, Boston, U.S.A.). May 7, 1931, No. 13540. [Class 64 (ii).] In a method of controlling the relative humidity of the air of a textile factory or other enclosure, interior humidifying means and ventilating means are controlled by humidity variation in such a way that departure from a predetermined standard of humidity restricts humidification or ventilation according as the change of humidity is upward or downward. Preferably there is also provided a temperaturesensitive control to restrict ventilation if the temperature is below a predetermined level. The regulator, Fig. 2, comprises a casing having a dry bulb compartment 22 and a wet bulb compartment 23 housing thermo-sensitive members 24, 25 acting on the ends of pivoted levers 26, 27. The upper end of the lever 26 is provided with three valve plates having ports 30, 31, 32 co-operating with valves 33, 34, 35 respectively, the uppermost valve being connected by an adjustable rod to the casing and the lower valves being similarly connected to the upper end of the lever 27. A spray 39 is adapted to discharge water into the compartment 23 and also to circulate by injector action a current of air from the enclosure, into the compartment 22 through an opening 40 and thence into the wet bulb compartment 23 through an opening 41. Relays 44, 45 under the control of the regulator govern the passage of compressed air to a water supply valve 48 of the humidifying supply and to the operating mechanism of the ventilating means. Each relay, Fig. 3, comprises a casing 58 having a passage 61 connecting the inlet and outlet pipes such as 43, 50. This passage is normally closed by a conical valve 63 but is adapted to be opened by the action of compressed air on a diaphragm motor 57 which acts against a spring 68 to push back the valve 63 by means of a stem 66 and a valve rod 65. The compressed air supply pipe 42 is connected to the inlets of the relays by pipes 43 and also through restricted branches 52, 55 to pipes 53, 56 which are connected to the ports 30, 32 respectively and also to the diaphragm motors of the relays 44, 45. respectively. The outlet of the relay 44 is connected to the humidifying control valve 48 by a pipe 46 while the outlet of the relay 45 is connected by a restricted pipe 50 to a pipe 51 leading to the valve 31 and also to the ventilator actuating mechanism. In operation, the position of the valve 33 is so adjusted that if the humidity is below a certain standard, the port 30 will be closed, thus allowing pressure to build up in the pipe 53 and operate the relay 44 to allow compressed air to flow through the pipe 46 to operate the humidifiers. The uppermost valve 35 is so adjusted that below a certain temperature the port 32 is always open and no pressure can build up in the pipe 56 to operate the relay 45. Above this temperature the relay operates to allow compressed air to enter the pipe 51. Sufficient pressure for the operation of the ventilators cannot be produced in the pipe 51, however, unless the humidity is above a certain value and the port 31 is consequently closed. In a modified form of regulator, Fig. 6, two ventilator controls are provided and operate at different humidities. The lever 26 is provided with an additional valve plate with a port 105 co-operating with a valve 106 adjustably connected to the upper end of the lever 27. As before the valve 33 and relay 44 control the humidifiers and the valve 35 is so arranged as to prevent the actuation of the relay 45 until the temperature of the enclosure exceeds a predetermined standard. Above this temperature the valves 106, 34 are adjusted to act in succession to close ports 104, 31 thus successively actuating additional relays 112, 111 respectively and allowing compressed air from a pipe 42 to pass to pipes 115, 119 leading to a two-stage ventilatoractuating device.